Genetic testing, also known as DNA testing, is a voluntary examination of one’s Deoxyribonucleic Acid (DNA) to establish its differences and changes in its sequence and (or) susceptibility to abnormalities or diseases. The test includes finding out the changes in chromosomes, genes, and proteins. Genetic testing can predict one’s probability of passing down or developing a genetic disorder.
The Importance of Consent During Genetic Testing
Before genetic testing is carried out on a person, they should have informed consent. A person must be counseled and informed well about the details of such a test. Informed consent involves making them understand the test procedures, expected test results, and what the tests would mean. Understanding clearly what the test entails, one can decide whether to take on the test or not by signing a consent form. It is important to note that parents or guardians make decisions for minors.
What Happens During Genetic Testing?
Genetic testing is mainly carried out on samples of hair, skin, amniotic fluid, blood, or any other tissues. The samples are taken to a laboratory where experts and technicians under specified machines look into the genetic changes, their anticipated effects or establish the presence of an earlier suspected disorder or health condition.
Types of Genetic Testing
There are several types of genetic testing. One requires more than one to establish their condition. These are:
Such tests examine the whole chromosome or the long DNA strands to find the large-scale mutation. Large scale gene mutations include added large chromosome pieces (duplication), rearrangements of the sequence (translocation), and deletion, that is, missing chromosome. Usually, some chromosomal changes indicate certain genetic disorders like Turner’s Syndrome.
Molecular tests are targeted to find changes in a specific gene. The tests determine the DNA sequencing, order, and nucleotides. Molecular tests have varying scopes, such as:
- Targeting one variant to look for a change in one gene
- Single-gene examination
- Looking for a variant in more than a gene (gene panel)
- Whole-genome sequencing, which examines a bulk of DNA where the panel and single gene tests give unclear results
Biochemical testing focus on proteins and enzymes produced by genes. Changes in the amounts of protein synthesized or activities of the enzymes can be used to deduce DNA changes and underlying genetic conditions. Low concentrations of a particular enzyme can indicate a specific gene variant.
Gene Expression Tests
Gene expression tests find out genes‘ activation and deactivation (expression). Abnormal gene expression, too much or minimal, indicates a different genetic abnormality. The time taken to receive test results depends on the test type and health facility. It would be best to ask your health counselor the meaning of expected or found results before or after the test. Test results can be used to establish the presence of an underlying genetic condition. However, it is not easy to unequivocally declare the presence of a genetic disorder based on test results since tests do not always give precise information.
Therefore, the health counselor needs to ask about one’s family medical history, personal medical history, or past genetic test one underwent while interpreting the results. Genetic test results can either be positive or negative. Positive results insinuate that the mutation being tested is detected. A positive result can be a diagnosis for a particular genetic condition. Negative test results show an absence of mutation detected in the tested gene or chromosome. However, a lack of mutation does not always assure someone that they will never develop a genetic disease. Genetic tests can also give false-negative results in which the test shows limited or reduced risk while one is actually at risk of being affected. There can also be inconclusive results where the detected mutation or variant has no genetic disorder associated with it.
This means that the variant is not disease-causing. It is best to test a family member or consider follow-up tests to ascertain one’s condition in such cases. Regardless of the test results, it would help if you talked to your counselor about what the test results might mean for your health and got professional advice on the next step. Living a healthy lifestyle is a goal of many. One of the primary steps of achieving this is to ensure constant health checks. Ready to get started? It would be best to consider having regular genetic tests to know your status and take advised steps. Call us today on 205-352-9141 if you have any inquiries on genetic testing today.